Started happening late last week.

This report is automatically generated to track the following Failure:
Test: desktopui_MashLogin.
Suite: chrome-informational.
Chrome Version: 70.0.3527.0.
Build: veyron_minnie-tot-chrome-pfq-informational/R70-10979.0.0-b2858056.

Reason:
Unhandled DevtoolsTargetCrashException: Devtools target crashed.
build artifacts:
https://storage.cloud.google.com/?arg=chromeos-image-archive/veyron_minnie-tot-chrome-pfq-informational/R70-10979.0.0-b2858056.
results log: http://ubercautotest.corp.google.com/tko/retrieve_logs.cgi?job=/results/228791738-chromeos-test/chromeos4-row9-rack10-host6/debug/.
status log: http://ubercautotest.corp.google.com/tko/retrieve_logs.cgi?job=/results/228791738-chromeos-test/chromeos4-row9-rack10-host6/status.log.
job link: http://cautotest-prod/afe/#tab_id=view_job&object_id=228791738.

You may want to check the test history:
https://stainless.corp.google.com/search?test=^desktopui\_MashLogin$&first_date=2018-07-22&last_date=2018-08-19&row=model&col=build&view=matrix

CPU: arm
     ARMv1 ARM part(0x4100c0d0) features: swp,half,thumb,fastmult,vfpv2,edsp,thumbee,neon,vfpv3,tls,vfpv4,idiva,idivt
     4 CPUs

GPU: UNKNOWN

Crash reason:  SIGSEGV
Crash address: 0x0
Process uptime: not available

Thread 0 (crashed)
 0  chrome!ui::DrmThread::IsDeviceAtomic(int, bool*) [drm_device.h : 81 + 0x0]
     r0 = 0x00000000    r1 = 0x00000000    r2 = 0x00000001    r3 = 0x00000000
     r4 = 0xa64165e3    r5 = 0xacaecec0    r6 = 0x0d12f804    r7 = 0xa5c16a60
     r8 = 0x00000000    r9 = 0xa5c16af0   r10 = 0xa5c16c10   r12 = 0x0e22fab4
     fp = 0xacaecec0    sp = 0xa5c16a50    lr = 0x0693fe75    pc = 0x0693fe78
    Found by: given as instruction pointer in context
 1  chrome!ui::(anonymous namespace)::OnRunPostedTaskAndSignal(base::OnceCallback<void ()>, base::WaitableEvent*) [callback.h : 99 + 0x3]
     r4 = 0xa64165a8    r5 = 0x0eaddfc0    r6 = 0x0d12f804    r7 = 0xa5c16a70
     r8 = 0x00000000    r9 = 0xa5c16af0   r10 = 0xa5c16c10    fp = 0xacaecec0
     sp = 0xa5c16a68    pc = 0x0695211b
    Found by: call frame info
 2  chrome!base::internal::Invoker<base::internal::BindState<void (*)(base::OnceCallback<GURL ()>, std::__1::unique_ptr<GURL, std::__1::default_delete<GURL> >*), base::OnceCallback<GURL ()>, std::__1::unique_ptr<GURL, std::__1::default_delete<GURL> >*>, void ()>::RunOnce(base::internal::BindStateBase*) [bind_internal.h : 416 + 0x1]
     r4 = 0xacaecec0    r5 = 0x0e417120    r6 = 0x0d12f804    r7 = 0xa5c16a88
     r8 = 0x00000000    r9 = 0xa5c16af0   r10 = 0xa5c16c10    fp = 0xacaecec0
     sp = 0xa5c16a78    pc = 0x0646182d
    Found by: call frame info
 3  chrome!base::debug::TaskAnnotator::RunTask(char const*, base::PendingTask*) [callback.h : 99 + 0x3]
     r4 = 0x0d16ed58    r5 = 0x0e417120    r6 = 0x0d12f804    r7 = 0xa5c16b30
     r8 = 0x00000000    r9 = 0xa5c16af0   r10 = 0xa5c16c10    fp = 0xacaecec0
     sp = 0xa5c16a90    pc = 0x0816a52b
    Found by: call frame info
 4  chrome!base::MessageLoop::RunTask(base::PendingTask*) [message_loop.cc : 431 + 0x5]
     r4 = 0x0d16ea34    r5 = 0xa5c16bb0    r6 = 0xa5c16ba0    r7 = 0xa5c16be0
     r8 = 0x0e1ac768    r9 = 0x0e1ac700   r10 = 0xa5c16c10    fp = 0xacaecec0
     sp = 0xa5c16b38    pc = 0x080fca71
    Found by: call frame info
 5  chrome!base::MessageLoop::DoWork() [message_loop.cc : 442 + 0x5]
     r4 = 0x0ceb3eb4    r5 = 0xa5c16c38    r6 = 0xa5c16c48    r7 = 0xa5c16d70
     r8 = 0x0e1ac78c    r9 = 0x0e1ac700   r10 = 0xa5c16cc8    fp = 0xa5c16cb0
     sp = 0xa5c16be8    pc = 0x080fd317
    Found by: call frame info
 6  chrome!base::MessagePumpLibevent::Run(base::MessagePump::Delegate*) [message_pump_libevent.cc : 210 + 0x3]
     r4 = 0x0e2118a0    r5 = 0x0e1ac700    r6 = 0x00000000    r7 = 0xa5c16dc0
     r8 = 0x0cd67478    r9 = 0x0e2118a8   r10 = 0x00000000    fp = 0x00000000
     sp = 0xa5c16d78    pc = 0x081681d7
    Found by: call frame info
 7  chrome!base::RefCountedThreadSafe<base::TaskRunner, base::TaskRunnerTraits>::Release() const [run_loop.cc : 102 + 0x3]
     r4 = 0xa5c16df0    r5 = 0x0d16d03c    r6 = 0x0e1e8968    r7 = 0xa5c16dd0
     r8 = 0x0c730c21    r9 = 0xa5c16df0   r10 = 0x0e1ac700    fp = 0xa5c16df0
     sp = 0xa5c16dc8    pc = 0x081146f1
    Found by: call frame info
 8  chrome!base::Thread::ThreadMain() [thread.cc : 357 + 0x21]
     r4 = 0x0e1e8960    r5 = 0x0d16d03c    r6 = 0x0e1e8968    r7 = 0xa5c16e40
     r8 = 0x0c730c21    r9 = 0xa5c16df0   r10 = 0x0e1ac700    fp = 0xa5c16df0
     sp = 0xa5c16dd8    pc = 0x0813fb61
    Found by: call frame info
 9  chrome!base::(anonymous namespace)::ThreadFunc(void*) [platform_thread_posix.cc : 76 + 0x23]
     r4 = 0x0d16ddc8    r5 = 0xa5c17450    r6 = 0x0e1e53c0    r7 = 0xa5c16e58
     r8 = 0x0e1e8960    r9 = 0xa6417684   r10 = 0xa6417450    fp = 0x00000000
     sp = 0xa5c16e48    pc = 0x081654ed
    Found by: call frame info
10  libpthread-2.23.so!start_thread [pthread_create.c : 335 + 0xb]
     r4 = 0xa5c17450    r5 = 0xa6416710    r6 = 0x00000000    r7 = 0xa5c16e60
     r8 = 0xa5c16f90    r9 = 0xa6417684   r10 = 0xa6417450    fp = 0x00000000
     sp = 0xa5c16e60    pc = 0xaca93551
    Found by: call frame info
11  libc-2.23.so!clone + 0x5e
     r4 = 0xa5c17450    r5 = 0xa6416710    r6 = 0x00000000    r7 = 0x00000078
     r8 = 0xa5c16f90    r9 = 0xa6417684   r10 = 0xa6417450    fp = 0x00000000
     sp = 0xa5c16f90    pc = 0xac5fc141
    Found by: call frame info

Test history:
https://stainless.corp.google.com/search?exclude_retried=true&exclude_cts=false&exclude_non_production=true&exclude_acts=true&exclude_non_release=true&exclude_au=true&test=desktopui_MashLogin&exclude_not_run=false&row=board&col=build&view=matrix&days=14

This test just runs Chrome through the login screen with --enable-features=Mash, which runs ash out-of-process.

I think derat@ just added a suite to the Chrome PFQ that includes a similar test, so it would be good if this didn't flake.

spang, can you route this to the right person?